A Letter from James M. Lehrer, Attorney at Law, Rosemead, CA

"I have been using your model ER•4S earphones for about two months, and I wanted to take this opportunity to tell you how pleased I am with them.

"My hobby is classical music. For the past several years, I have studied flute with the principal flutist of a major symphony orchestra. I have a small digital-based project studio, with which I listen to recorded music, and record my practice sessions for self-critique. I also do location recording of soloists and ensembles.

"Because I am interested in preserving my hearing, I had already invested in a pair of custom hearing protectors, which is how I first became aware of your company [ER•15's]. Later, I read a review of your earphones in a recording trade magazine. The ER•4S earphones appealed to me because I thought they would meet my need for a very compact (i.e., pocketsize) and high-grade unit that I could comfortably use on my many airplane trips.

"The ER•4S earphones impressed me so much, that I not only use them for air travel with my Minidisc recorder, I use them for all my monitoring purposes (CD player, CD deck, and DAT Location Recorded). I find them quite comfortable with the silicon ear tips. Most importantly, the isolation they provide enables me to enjoy all the details of the recorded material without turning the audio gain to an unnecessarily high level. The stereo imaging and detail revealed by your earphones are spectacular, particularly with recordings made to audiophile standards.

"I would also like to compliment you on the excellent design of the earphones storage box, accessories, and the earphone itself. It is a highly versatile and fully professional unit, which more than matches the capabilities of my other listening and recording equipment."

An email from Robert Malos

"I've been an ER•4S owner for over a year now (through Headroom) and I just wanted to thank you for making such a wonderful product. I don't know exactly how you did it but these are absolutely the most accurate speakers I have ever heard. And my home system includes the Gallo Acoustic Solo model which are *extremely* accurate.

It is such a pleasure to hear this level of audio quality! And they're very comfortable. I had previously bought some Grado 225 headphones for home use and although I like their sound they are quite uncomfortable for extended use. And-of-course the isolation properties of the ER•4S are nonpareil. Great job!"

A Letter from Dave Arnovitz discussing Etymotic ER•4S vs. Sennheiser HD580

"Turns out each has it's own advantages and disadvantages. The Etymotics are very fast and accurate. In addition, they are very portable. All that plus they allow very detailed listening in medium to high background noise. However, the cable is short, not very sanitary to allow other uses to listen (they always want to) without changing plugs. I have never found them uncomfortable. The 580-600's are a bit more musical and others can easily check out your tunes. However, they are hot in the summer and are not portable friendly. I could go on and on but the bottom line is that you need both depending on the conditions you are encountering. I was recently on a bus going through Denalia National Park listening to Diane Schuur at rather high levels with the 600's and I found out later I was upsetting some with my tunes as it can easily be heard by others nearby. Just buy both and you will be ready for anything!!!!"

Letter from Steven Aukstakalnis, Taipei, Taiwan

"Nearly five years ago I received a pair of ER•4B earphones as a gift. It is without a doubt the most incredible listening aid I have ever encountered. My work takes me all over the world and I have spent many, many hours in complete bliss listening to flawless delivery of music while on loud aircraft, or on trains in the third world, or on the back of camels, etc.

"I have carried these"canal phones"with me to over 30 countries. I have shared the listening experience with many - from the captain of an old junk in Aberdeen Harbor in Hong Kong, to Indians in the highlands of Ecuador, a few members of the U.S. Senate and innumerable airline pilots.

"Currently, I am in dire need of replacement parts. My life will be reduced to a smoldering lump of sloth dung without replacement parts. It is my desire to continue to preach the good word about this fine product. So, I come to you on my hands and knees praying that you still produce these parts and that I can somehow acquire a new supply."

Letter from David D:

"In my 50+ years, I have never written a testimonial to any product. Yours is the first.

My comments were written two days after the earphones arrived. With use or my ear's growing accommodation, my comment on the sound in the upper range has softened. Although they are essentially equal to my former Stax with the Stax amp ... perhaps the only insignificant difference I can detect is at the upper end. Thanks for a superb product!! They have solved my location recording problems. My Stax units took up as much room as Schoeps/DAT based recording system ... and they required AC power."

Letter from Tom Hagan, Saranac, MI

"I find the 4S' the most valuable piece of equipment I own. The lady that answers the phone is terrific: sweet, helpful and humorous. I wish the best to your company because of the work you do and the class with which you do it."

Letter from Stephen Paul, Bangor, ME

"The ER•4B earphones I recently purchased are so outstanding I had to write. I simply cannot believe the level of resolution the ER•4's are capable of providing the listener - especially when using good program material. This is a product that all recording engineers should be using in the final mastering.

"As an undergraduate in college, I had a tremendous interest in the field of psychoacoustics and came very close to entering a Ph.D. program in that discipline. I would greatly appreciate any available literature you may be able to send relative to the ER•4B's and S's as well as more detailed technical information on the psychoacoustic principles you employed in the development of this unique, exceptional product."

Letter from Susan Brown

"I want to thank you for the ER•4S headphones. I enjoy the detail, balance and accuracy that the ER•4S' offer. I did not think that you could fit a pair of Wilson/Watts in your shirt pocket. I am glad that I have been proven wrong! Please let me know if you build any new products that would be of interest to an audiophile."

Also from Susan Brown

"I was just in Denmark and had many hours in travel. Your headphones made the trip a pleasure. If you are going to make any changes, please call me."

A Letter from Adrian Mattocks, Charlotte, NC:

"I normally do not write such letters, but in this case I have no choice. I'm a drummer and mastering engineer and I just received my set of ER•4S's. I have just one thing to say: ABSOLUTELY AMAZING!!!!!!!!!!

"I have listened through everything from worthless AKG's to Grado's and the ER•4S's leave them all behind! In my opinion, they rival Genelec, Tannoy, and BagEnd in terms of accuracy, frequency response and detail. Not to mention, the isolation (when I'm playing drums) is phenomenal!

"I can't say enough about them! They even sound great through a crappy stereo with horrid converters!"